skeshesh
Senior Member
- Location
- Los Angeles, Ca
Good day everyone.
I'm working on a remodel of an existing building (several floors getting torn out and rebuilt). We're going to have a bunch of new equip in there and the question related to the KAIC rating of this equip. Distribution class will switch over from 4.8kV to 12.5kV in the future and I'm unsure of the effect on the system.
Existing dual primary transformer is rated at 12.47/4.8kV. In my understanding from the nameplate the %Z (6.1@rated kVA) does not change with the switchover. I'm trying to understand this concept better. I thought the %Z is determined by the mfg. by shorting the secondary and applying test voltage until rated current is circulating and then taking the ration of that voltage with the rated. If I'm correct about the procedure, then how do we have one %Z for the dual primary transformer? Am I correct in believing that the available short circuit downstream of this transformer will not change if the primary feed is changed to 12.5kV?
I'm working on a remodel of an existing building (several floors getting torn out and rebuilt). We're going to have a bunch of new equip in there and the question related to the KAIC rating of this equip. Distribution class will switch over from 4.8kV to 12.5kV in the future and I'm unsure of the effect on the system.
Existing dual primary transformer is rated at 12.47/4.8kV. In my understanding from the nameplate the %Z (6.1@rated kVA) does not change with the switchover. I'm trying to understand this concept better. I thought the %Z is determined by the mfg. by shorting the secondary and applying test voltage until rated current is circulating and then taking the ration of that voltage with the rated. If I'm correct about the procedure, then how do we have one %Z for the dual primary transformer? Am I correct in believing that the available short circuit downstream of this transformer will not change if the primary feed is changed to 12.5kV?